Phi: Difference between revisions

From formulasearchengine
Jump to navigation Jump to search
en>Nanite
→‎Use as a symbol: work function
en>Kwamikagami
No edit summary
Line 1: Line 1:
[[File:Shutter speed waterfall.gif|frame|Shutter speed can have a dramatic impact on the appearance of moving objects. Changes in background blurring are apparent from the need to adjust the [[aperture]] size to achieve proper exposure.]] <!-- Don't thumb this, mediawiki animation  scaling is broken and will make it ugly and bigger -->
If you have to accelerate your PC then you have come to the proper area. I will show you, now, five rapid ways that you can dramatically better a computer's performance.<br><br>The PC registry begins to receive mistakes plus fragmented the more you use the computer considering you enter more information every time, and also create changes in the systems and setup. When the registry begins to receive overloaded plus full of mistakes, a computer might eventually crash. It can be done to fix it on a own yet rather risky, specifically should you have no extensive experience in doing so. Therefore, do NOT even attempt to do this yourself.<br><br>The error is basically a outcome of problem with Windows Installer package. The Windows Installer is a tool employed to install, uninstall plus repair the most programs on the computer. Let you discuss a few points which helped a great deal of people that facing the synonymous matter.<br><br>There may be several reasons why a computer will lose speed. Normal computer employ, such as surfing the Internet may get the running program in a condition where it has no choice yet to slow down. The continual entering plus deleting of temporary files which occur when we surf the Web leave the registries with thousands of false indicators in the running system's registry.<br><br>To fix the problem that is caused by registry error, we want to use a [http://bestregistrycleanerfix.com/registry-reviver registry reviver]. That is the safest and easiest way for average PC users. But there are thousands of registry products available available. You need to discover a good one which can definitely solve the problem. If you use a terrible 1, you will expect more issues.<br><br>Another key element when we compare registry cleaners is having a center to manage your start-up jobs. This simply signifies that you can choose what programs you want to commence when we commence the PC. If you have unwanted programs beginning when you boot up the PC this may lead to a slow running computer.<br><br>Perfect Optimizer is a superior Registry Product, updates consistently plus has many features. Despite its cost, we will find which the update are certainly worthwhile. They provide plenty of support via telephone, mail and forums. You might want to head over to the free trial to check it out for yourself.<br><br>Registry products may help a computer run inside a better mode. Registry cleaners must be part of the standard scheduled maintenance program for your computer. You don't have to wait forever for a computer or the programs to load and run. A little repair usually bring back the speed you lost.
[[File:Nikkormat shutterspeeddial top.jpg|thumb|upright|The shutter speed dial of a [[Nikkormat|Nikkormat EL]]]]
[[File:Truck with motion blur.jpg|thumb|Slow shutter speed combined with panning the camera can achieve a motion blur for moving objects.]]
 
In [[photography]], '''shutter speed''' or '''exposure time''' is the length of time a [[camera]]'s [[shutter (photography)|shutter]] is open when taking a photograph.<ref name=ray>
{{cite book | title = Manual of Photography: A Textbook of Photographic and Digital Imaging | chapter = Camera Features | pages = 131–132 | author = Sidney F. Ray | editor = Ralph Eric Jacobson et al. | url = http://books.google.com/books?id=HHX4xB94vcMC&pg=PA132&ots=7Gq_Az_-zl&dq=standard-series+%22shutter+speed%22&sig=bQ5bvKIS-y1_Q4km6Pm-yCZDcGo | publisher = Focal Press | edition = Ninth ed. | isbn = 0-240-51574-9 | year = 2000 }}
</ref>
The amount of light that reaches the [[Photographic film|film]] or [[image sensor]] is proportional to the exposure time.
 
==Introduction==
The camera's shutter speed, the lens's brightness ([[f-number]]), and the scene's [[luminance]] together determine the amount of light that reaches the film or sensor (the [[exposure (photography)|exposure]]). [[Exposure value]] (EV) is a single quantity that accounts for the shutter speed and the f-number.
 
Multiple combinations of shutter speed and f-number can give the same exposure value. Doubling the exposure time doubles the amount of light (subtracts 1 EV).  Making the f-number one stop brighter (reducing the f-number by a factor of <math>\scriptstyle \sqrt{2}</math>) also doubles the amount of light.  A shutter speed of 1/50 s with an {{f/}}4.0 lens gives the same exposure value as a 1/100 s shutter with an {{f/}}2.8 lens, and also the same exposure value as a 1/200 s shutter with an {{f/}}2.0 lens.
 
In addition to its effect on exposure, the shutter speed changes the way movement appears in photographs. Very short shutter speeds can be used to freeze fast-moving subjects, for example at sporting events. Very long shutter speeds are used to intentionally blur a moving subject for artistic effect.<ref>{{cite book | title = The Complete Guide to Night and Low-Light Photography | author = Lee Frost | publisher = Amphoto Books | year = 2000 | isbn = 0-8174-5041-6 | url = http://books.google.com/books?id=IugNeG0vIMcC&pg=RA1-PA142&ots=aA3puq4Dv2&dq=intentionally+blur+moving+%22shutter+speed%22&sig=ZujwjyJB5n7dQ-3-km1vyLoSEEc#PRA1-PA141,M1 }}</ref> Short exposure times are sometimes called "fast", and long exposure times "slow".
 
Adjustment to the aperture controls the [[depth of field]], the distance range over which objects are acceptably sharp; such adjustments need to be compensated by changes in the shutter speed.
 
In early days of photography, available shutter speeds were not standardized, though a typical sequence might have been 1/10 s, 1/25 s, 1/50 s, 1/100 s, 1/200 s and 1/500 s. Following the adoption of a standardized way of representing [[aperture]] so that each major step exactly doubled or halved the amount of light entering the camera ({{f/}}2.8, {{f/}}4, {{f/}}5.6, {{f/}}8, {{f/}}11, {{f/}}16, etc.), a standardized 2:1 scale was adopted for shutter speed so that opening one aperture stop and reducing the shutter speed by one step resulted in the identical exposure. The agreed standards for shutter speeds are:<ref name=kahn>{{cite book | title = Essential Skills for Nature Photography | author = Cub Kahn | url = http://books.google.com/books?id=EZhNY--TZjIC&pg=PT21&dq=%22standard+series%22+%22shutter+speed%22+1-1000&ei=h0MHSejTFI_gswOh3eDzDQ | isbn = 1-58428-009-3 | year = 1999 | publisher = Amherst Media}}</ref>
{{columns-list|4|
*1/1000 s
*1/500 s
*1/250 s
*1/125 s
*1/60 s
*1/30 s
*1/15 s
*1/8 s
*1/4 s
*1/2 s
*1 s
}}
 
[[Image:Phatman - Lightning on the Columbia River (by-sa).jpg|thumb|left|upright|An extended exposure can also allow photographers to catch brief flashes of light, as seen here. Exposure time 15 seconds.]]
 
With this scale, each increment roughly doubles the amount of light (longer time) or halves it (shorter time).
 
Camera shutters often include one or two other settings for making very long exposures:
* '''B''' (for ''[[bulb (photography)|bulb]]'') keeps the shutter open as long as the shutter release is held.
* '''T''' (for ''time'') keeps the shutter open until the shutter release is pressed again.
 
The ability of the photographer to take images without noticeable blurring by camera movement is an important parameter in the choice of slowest possible shutter speed for a handheld camera. The rough guide used by most [[135 film|35 mm]] photographers is that the slowest shutter speed that can be used easily without much blur due to camera shake is the shutter speed numerically closest to the lens focal length. For example, for handheld use of a 35&nbsp;mm camera with a 50&nbsp;mm [[normal lens]], the closest shutter speed is 1/60 s. This rule can be augmented with knowledge of the intended application for the photograph, an image intended for significant enlargement and closeup viewing would require faster shutter speeds to avoid obvious blur. Through practice and special techniques such as bracing the camera, arms, or body to minimize camera movement longer shutter speeds can be used without blur. If a shutter speed is too slow for hand holding, a camera support, usually a [[Tripod (photography)|tripod]], must be used. [[Image stabilization]] can often permit the use of shutter speeds 3–4 stops slower (exposures 8–16 times longer).
 
Shutter priority refers to a shooting mode used in semi-automatic cameras. It allows the photographer to choose a shutter speed setting and allow the camera to decide the correct aperture. This is sometimes referred to as [[shutter priority|Shutter Speed Priority Auto Exposure]], or TV (time value) mode.
 
==Creative utility in photography==
{{main|Motion blur}}
 
{{multiple image
| align    = right
| direction = horizontal
| image1    = E17 - korte sluitertijd.JPG
| alt1      =
| caption1  =
| image2    = E17 - lange sluitertijd.JPG
| alt2      =
| caption2  =
| footer    = The photograph to the right was taken with a slower shutter speed than that to the left, creating a more pronounced motion blur effect and longer streaks of light from vehicle headlights.
}}
[[File:Sparklers with a slow shutter speed.JPG|thumb|Sparklers moved in a circular motion with an exposure time of 4 seconds. This is an example of [[Light painting]]]]
 
Shutter speed is one of several methods used to control the amount of light recorded by the camera's [[Image sensor|digital sensor]] or film. It is also used to manipulate the visual effects of the final image beyond its luminosity.
[[Image:Shutter speed pool.jpg|thumb|Images taken with a lower shutter speed invoke a visual sense of movement. Exposure time 3 seconds.]]
Slower shutter speeds are often selected to suggest movement in a still photograph of a moving subject.
 
Excessively fast shutter speeds can cause a moving subject to appear unnaturally frozen. For instance, a running person may be caught with both feet in the air with all indication of movement lost in the frozen moment.
 
When a slower shutter speed is selected, a longer time passes from the moment the shutter opens till the moment it closes. More time is available for movement in the subject to be recorded by the camera.
 
A slightly slower shutter speed will allow the photographer to introduce an element of blur, either in the subject, where, in our example, the feet, which are the fastest moving element in the frame, might be blurred while the rest remains sharp; or if the camera is [[panning (camera)|panned]] to follow a moving subject, the background is blurred while the subject remains sharp.
 
The exact point at which the background or subject will start to blur depends on the rate at which the object is moving, the angle that the object is moving in relation to the camera, the distance it is from the camera and the focal length of the lens in relation to the size of the digital sensor or film.
 
When slower shutter speeds, in excess of about half a second, are used on running water, the photo will have a ghostly white appearance reminiscent of [[fog]]. This effect can be used in [[landscape photography]].
 
[[Zoom burst]] is a technique which entails the variation of the focal length of a zoom lens during a longer exposure. In the moment that the shutter is opened, the lens is zoomed in, changing the focal length during the exposure. The center of the image remains sharp, while the details away from the center form a radial blur, which causes a strong visual effect, forcing the eye into the center of the image.<ref>{{cite web | work = Illustrated Photography | title = About Shutter Speed | url=http://www.illustratedphotography.com/basic-photography/understanding-shutter-speed}}</ref>
 
The following list provides an overview of common photographic uses for standard shutter speeds.
* ''1/16000 s'': The fastest speed available in [[APS-H]] or [[APS-C]] format [[DSLR]] cameras (as of 2012). ([[Canon (company)|Canon]] [[Canon EOS 1D|EOS 1D]], [[Nikon]] [[Nikon D1|D1]], Nikon 1 J2, [[Nikon D1X|D1X]], and [[Nikon D1H|D1H]])
* ''1/12000 s'': The fastest speed available in any [[35 mm]] film [[Single-lens reflex camera|SLR]] camera. ([[Minolta]] [[Minolta 9xi|Maxxum 9xi]], {{ill|de|Minolta Maxxum 9{{!}}Maxxum 9|Minolta Dynax 9}}''
* ''1/8000 s'': The fastest speed available in production [[Single-lens reflex camera|SLR]] cameras (as of 2013), also the fastest speed available in any [[Full-frame digital SLR|full-frame DSLR]] or [[Sony SLT camera|SLT]] camera (as of 2013). Used to take sharp photographs of very fast subjects, such as birds or planes, under good lighting conditions, with an [[ISO film speed|ISO speed]] of 1,000 or more and a large-aperture lens.<ref>Doeffinger, 5</ref>
* ''1/4000 s'': The fastest speed available in [[consumer]] SLR cameras (as of 2009); also the fastest speed available in any [[leaf shutter]] camera (such as the [[Sony Cyber-shot DSC-RX1]]) (as of 2013). Used to take sharp photographs of fast subjects, such as athletes or vehicles, under good lighting conditions and with an ISO setting of up to 800.<ref>Doeffinger, 6</ref>
* ''1/2000 s and 1/1000 s'': Used to take sharp photographs of moderately fast subjects under normal lighting conditions.<ref>Doeffinger, 7–12</ref>
* ''1/500 s and 1/250 s'': Used to take sharp photographs of people in motion in everyday situations. 1/250&nbsp;s is the fastest speed useful for [[Panning (camera)|panning]]; it also allows for a smaller aperture (up to f/11) in motion shots, and hence for a greater depth of field.<ref>Doeffinger, 12–17</ref>
* ''1/125 s'': This speed, and slower ones, are no longer useful for freezing motion. 1/125&nbsp;s is used to obtain greater depth of field and overall sharpness in [[landscape photography]], and is also often used for panning shots.
* ''1/60 s'': Used for panning shots, for images taken under dim lighting conditions, and for available light portraits.<ref>Doeffinger, 20–22</ref>
* ''1/30 s'': Used for panning subjects moving slower than {{convert|30|mph}} and for available-light photography. Images taken at this and slower speeds normally require a [[tripod]] or an [[Image stabilization|image stabilized]] lens/camera to be sharp.<ref>Doeffinger, 24</ref>
* ''1/15 s and 1/8 s'': This and slower speeds are useful for photographs other than panning shots where motion blur is employed for deliberate effect, or for taking sharp photographs of immobile subjects under bad lighting conditions with a tripod-supported camera.<ref>Doeffinger, 26–30</ref>
* ''1/4 s, 1/2 s and 1 s'': Also mainly used for motion blur effects and/or low-light photography, but only practical with a tripod-supported camera.<ref>Doeffinger, 32–40</ref>
* ''[[Bulb (photography)|B (bulb)]]'' (1 minute to several hours): Used with a mechanically fixed camera in [[astrophotography]] and for certain special effects.<ref>Doeffinger, 41 et seq.</ref>
<gallery widths="200px" heights="200px">
File:The NTT Spinning like a Top.jpg|30-second exposure of the rotating [[New Technology Telescope]]
File:Wave Swinger 0.8 Sec SFGAm.JPG|The Whirligig ride during night at [[SFGAm]] at an exposure time of 0.8 Seconds.
File:Streaks outside Waterloo.jpg|Light streaks outside Waterloo Rail Station in London
File:Tottenham Ct. Rd. Slow Shutter.jpg|Light streaks on Tottenham Ct. Rd. in London
File:Tottenham Ct. Rd. Slow Shutter2.jpg|Light streaks on Tottenham Ct. Rd. in London of turning Taxis
File:Tottenham Ct. Rd. Slow Shutter3.jpg|More Light streaks of a bus in London
File:Tottenham Ct. Rd. Slow Shutter4.jpg|Bus moving at high speed
File:Tottenham Ct. Rd. Slow Shutter5.jpg|Slow shutters cannot be handled by hand, a side rail is being used. Bus in London
</gallery>
 
==Cinematographic shutter formula==
{{further|Rotary disc shutter}}
Motion picture cameras used in traditional [[film]] [[cinematography]] employ a mechanical [[rotary disc shutter|rotating shutter]]. The shutter rotation is synchronized with film being pulled through the gate, hence shutter speed is a function of the [[frame rate]] and [[shutter angle]].
 
Where ''E'' = shutter speed (reciprocal of exposure time in seconds), ''F'' = frames per second, and ''S'' = shutter angle:<ref name=brown/>
 
: <math>E = \frac {F \cdot 360^\circ}{S}</math>, for ''E'' in reciprocal seconds
 
: <math>S = \frac {F \cdot 360^\circ}{E}</math>
 
With a traditional shutter angle of 180°, film is exposed for 1/48 second at 24 frame/s.<ref name=brown>{{cite book | title = Cinematography: Theory and Practice : Imagemaking for Cinematographers, Directors & Videographers | author = Blain Brown | publisher = Focal Press | year = 2002 | isbn = 0-240-80500-3 | url = http://books.google.com/books?id=1JL2jFbNPNAC&pg=PA125&ots=PCXRkW3nIk&dq=cinematography+360+shutter-angle+%22shutter+speed%22&sig=OTsZON3wEZbiNhkgOw8OfZB-amk }}</ref> To avoid effect of light interference when shooting under artificial lights or when shooting television screens and computer monitors, 1/50&nbsp;s (172.8°) or 1/60&nbsp;s (144°) shutter is often used.<ref>{{cite web | title = Shutter Speed vs. Shutter Angle | url = http://provideocoalition.com/index.php/freshdv/story/shutter_speed_vs_shutter_angle}}</ref>
 
Electronic video cameras do not have mechanical shutters and allow setting shutter speed directly in time units. Professional video cameras often allow selecting shutter speed in terms of shutter angle instead of time units, especially those that are capable of [[overcranking]] or undercranking.
 
==See also==
 
{{Commons|Shutter speed}}
*[[Exposure (photography)|exposure]]
*[[exposure value]]
*[[f-number]]
*[[shutter (photography)|shutter]]
 
==References==
 
{{reflist|2}}
 
*{{cite book|last=Doeffinger|first=Derek|title=Creative Shutter Speed: Master Your Camera’s Most Powerful Control|publisher=Wiley|year=2009|isbn=978-0-470-45362-9}}
 
{{photography subject}}
 
[[Category:Science of photography]]

Revision as of 23:24, 8 February 2014

If you have to accelerate your PC then you have come to the proper area. I will show you, now, five rapid ways that you can dramatically better a computer's performance.

The PC registry begins to receive mistakes plus fragmented the more you use the computer considering you enter more information every time, and also create changes in the systems and setup. When the registry begins to receive overloaded plus full of mistakes, a computer might eventually crash. It can be done to fix it on a own yet rather risky, specifically should you have no extensive experience in doing so. Therefore, do NOT even attempt to do this yourself.

The error is basically a outcome of problem with Windows Installer package. The Windows Installer is a tool employed to install, uninstall plus repair the most programs on the computer. Let you discuss a few points which helped a great deal of people that facing the synonymous matter.

There may be several reasons why a computer will lose speed. Normal computer employ, such as surfing the Internet may get the running program in a condition where it has no choice yet to slow down. The continual entering plus deleting of temporary files which occur when we surf the Web leave the registries with thousands of false indicators in the running system's registry.

To fix the problem that is caused by registry error, we want to use a registry reviver. That is the safest and easiest way for average PC users. But there are thousands of registry products available available. You need to discover a good one which can definitely solve the problem. If you use a terrible 1, you will expect more issues.

Another key element when we compare registry cleaners is having a center to manage your start-up jobs. This simply signifies that you can choose what programs you want to commence when we commence the PC. If you have unwanted programs beginning when you boot up the PC this may lead to a slow running computer.

Perfect Optimizer is a superior Registry Product, updates consistently plus has many features. Despite its cost, we will find which the update are certainly worthwhile. They provide plenty of support via telephone, mail and forums. You might want to head over to the free trial to check it out for yourself.

Registry products may help a computer run inside a better mode. Registry cleaners must be part of the standard scheduled maintenance program for your computer. You don't have to wait forever for a computer or the programs to load and run. A little repair usually bring back the speed you lost.